U.S. Pat. No. 4,427,249 discloses a cover for an active device substrate or leadless chip carrier connector. This cover includes a frame which fits down on the substrate or carrier positioned in the connector, and arms extending from the frame to the side walls of the connector housing. A latch, attached to each arm, includes a depending member with an inwardly projecting lip which catches beneath a downwardly facing shoulder on the side walls. Laterally projecting tabs, one on the depending member near the lip and another on the latch near the arm, provide a catch and fulcrum for a tool whereby the lip can be pried out from beneath the shoulders to release the cover.
U.S. Pat. No. 4,504,105 discloses a release member for use with the cover disclosed in the above-noted patent. The release member includes a depressible plate positioned on top of the cover with depending flaps on arms extending outwardly from the plate. The flaps have notches which receive the laterally projecting tabs on the depending members on the cover. Upon depressing the plate, the flaps pivot up and out, drawing the lips out from beneath the shoulders to release the cover.
In both of the aforementioned patents, the covers are shown as being completely releasable from the connector. This feature is not objectionable in situations in which the chip carrier is placed in the connector and is never removed. However, for burn-in sockets and the like, in which chip carriers are inserted and removed from the connector on a continual basis, a releasable or removable cover or retention member is not desired. This is particularly true in situations in which the connectors are densely spaced due to the minimal space available on the printed circuit board. With closely spaced connectors, it becomes difficult to handle loose covers, and consequently, damage can be done to the connectors as well as the board due to the clumsiness of the operator.
U.S. Pat. No. 4,621,884 teaches of a hinged cover for use with a socket. The hinged cover has latching features which are similar to those noted above, and is hinged to the socket so that as the cover is moved to the open position, the cover will not be removed from the socket. However, although this cover is not removable, it is possible that during the operation of the cover, the operator could incorrectly open the cover, causing the cover to be removed from the socket. As the cover disclosed in the patent is complex, and substantial in size, in order to generate the force required to insure for the proper electrical connection between the leads and the terminals, the cost of the cover is substantial. It is also worth noting the in order to remove the chip carrier from the socket a special tool must be utilized.
Accordingly, it would prove beneficial to provide the chip carrier socket with a simple and inexpensive means to retain the chip carrier in the chip carrier socket in environments in which vibration and the like are present. The retention means should be secured to the chip carrier socket so that during the operation of the retention means, the retention means could not be removed from the chip carrier socket.
It is also desirable to provide the retention means with a resilient latching means which is reliable over many cycles. Therefore, it is important that the resilient latching means be prevented from being overstressed during the operation thereof, thereby preventing the resilient latching means from taking a permanent set.